Measurement systems are used to optimize the performance of machines. It is typical for measurement systems to use data to optimize performance of an engine or transmission of a machine. Additionally, it is common for measurement systems to improve performance of other machine systems including braking, cooling, and suspension systems. In order to accomplish performance optimization, various components including sensors, controllers, receivers, and transmitters are used to gather and process data into useful information.
A rolling machine moves by rolling on wheels or tracks in order to be positioned to perform work. One aspect of a rolling machine that can be measured is the rolling resistance of the machine. The rolling resistance corresponds to a percentage of a generally horizontal force required to move a wheel compared to a generally vertical force acting on the wheel normal to the horizontal force. It is desirable to measure rolling resistance of rolling machines for various reasons. For example, determination of the rolling resistance of a machine may assist in making the machine more efficient and reduce operating costs by indicating ways to improve fuel economy, power train life, and tire life of the machine. Additionally, determination of rolling resistance may assist in improving roadway management, whereby irregular spots in the roadway that reduce machine efficiency may be identified and improved. Despite the advantageous reasons for measuring rolling resistance, it has proven difficult to determine.
One way to determine a machine's rolling resistance is disclosed in U.S. Pat. No. 5,787,378 (the '378 patent) issued to Schricker. The '378 patent describes a system and method for determining a resistance factor of a machine to detect an abnormal condition. The system includes sensors, a controller, and a transmitter. The '378 patent calculates a resistance factor using various inputs including vehicle weight, wind resistance, and net rimpull via onboard sensors or computer models. Additionally, the '378 patent uses a positioning means, such as a GPS, to determine the location of the machine. The '378 patent compares the individual machine resistance factor to a fleet average to detect an abnormal condition, such as, an under-inflated tire.
Although the measurement system of the '378 patent may help to determine a resistance factor of a machine, it may be complex and have an excessive number of sensors that may increase costs. For example, the '378 patent requires an individual machine's resistance factor to be compared to a continuously updated average fleet resistance factor to determine abnormal conditions. Continuously updating average fleet resistance is complex and requires considerable processing power. Further, in calculating the resistance factor, the '378 patent relies upon the determination of wind resistance using a sensor and coefficient of drag. Additionally, when calculating net rimpull, the '378 patent relies upon braking power as measured by sensors or determined by computer based models. The '378 patent's use of sensors or computer models to determine wind resistance and braking power to calculate the resistance factor increases complexity of the system.
The disclosed measurement system is directed to overcoming one or more of the problems set forth above.